LOS ANGELES (Reuters) - When three women of Russian feminist punk band Pussy Riot entered a Moscow church to perform a "punk prayer" in February of last year, little did they think their actions would land them behind bars and capture the world's attention.

A new documentary, "Pussy Riot - A Punk Prayer," which premiered at the Sundance Film Festival this week, follows the band members and their families as they struggle through the legal system in Russia.

The documentary tells the story of three women - Nadezhda Tolokonnikova, 22, Maria Alyokhina, 24, and Yekaterina Samutsevich, 30 - who as members of the feminist art collective Pussy Riot performed a 40-second "punk prayer" inside Russia's main cathedral on February 21, 2012.

Pussy Riot took on two powerful state institutions at once - the Russian Orthodox Church and the Russian government - when they burst into Moscow's golden-domed Christ the Savior Cathedral wearing bright ski masks, tights and colorful dresses to protest against President Vladimir Putin's close ties with the Church.

This performance led to their arrest on charges of religious hatred and culminated in a trial that reverberated around the world.

After a trial that was shown live on television, a judge ruled the three women had "committed an act of hooliganism, a gross violation of public order showing obvious disrespect for society."

The court found all three women guilty and sentenced them to two years in prison. Samutsevich later had her punishment converted to a suspended sentence.